The section continues to investigate pharmacological and behavioral treatments of substance abuse and interactions between these two forms of treatments. A primary objective of these studies is to eliminate drug use and decrease the probability of HIV transmission in cocaine- and/or heroin-dependent patients. Nearly all of the population studied inject drugs and are at high risk for contracting and spreading HIV infection. Two major non-pharmacological treatments of substance abuse, contingency management and cognitive/behavioral therapy, are under evaluation. Earlier research in our laboratory has shown that abstinence reinforcement contingencies are effective in producing significant periods of abstinence from cocaine and opiates in inner- city, intravenous, polydrug abusers receiving standard methadone maintenance treatment. A Cognitive/Behavioral counseling approach to substance abuse treatment developed in our laboratory is being integrated into the behavioral contingency management program to increase the duration of abstinence produced by the behavioral treatment alone by encouraging long-term changes in drug use and other HIV risk behaviors. The study is underway with approximately 70 of the planned 200 patients enrolled. In the past year we have completed two clinical trials. One trial evaluated the combination of contingency management and a pharmacological treatment (methadone maintenance) on treatment of opioid dependence. The second study evaluated the use of contingency management to reinforce decreases in drug use as an initial step toward complete abstinence from drug use. Data from these trials are currently being analyzed. Contingency management continues to show promise as an effective treatment for substance abuse. Future research efforts will address how best to combine this treatment approach with medications and other psychosocial treatments to produce long-term changes in behavior.